Improvement



KEHEW & FI'FIEL D.

Hot Air Register.

Patented July 22, 1862.

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UNITED STATES PATENT OFFICE.

WILLIAM B. KEHEYV AND CHARLES H. FIFIELD, OF SALEM, MASSACHUSETTS.

l MPROV EMENTJN HOT-AI R REGISTERS.

Specification forming part of Letters Patent No. 35,838., dated July 2?, 1862.

To all whom it may concern:

Be it known that we, \VILLIAM B. KEHEW and CHARLES H. FIFIELD, of Salem, in the county of Essex and State of Massachusetts, have invented a new and useful Improvement in Attachments to Registers or Outlet-Pipes of Hot-AirFurnaces; and we do hereby declare that the following is a full and exact description thereof, reference being had to theaccompanying drawing, and to letters of reference marked thereon, making a part of this specification, which represents in section-an apparatijus by which our invention may be carried on l The nature of our invention consists in a special arrangement for increasing the draft through the outlet-pipes of hot-air furnaces, and by the same means to combine the highlyheated air from the furnace (previous to its entrance to the apartment) with the cold air at the lower part of the room, modifying its temperature, andavoidi'ng the injurious efl'ect of the highly-heated air and making a better circulation and ventilation.

To enable others skilled in the art to make and use our invention, we will proceed to describe the same, reference being had to the drawing, which represents in section the attachment placed over the register of the outlet-pipe of a furnace.

We provide the register or outlet-pipe A with two upright tubes, B and 0, arranged one within the other, the inner tube, B, being the same diameter of the register A and fitting over it. The outer tube, 0, is made larger and higher, with openings or perforations D, extending entirely around the lower end.

We construct the tubes B and C of sheetiron, although other materials may be used, and for ordinary purposes we make the outer tube thirty inches high and the inner tube a little less than two-thirdsof that height, the

diameter of the inner tube, B, being the same i as that of theregister or outlet over which it is placed, and the outer tube, 0, is made large enough to leave a space of from one inch to two and a half inches between the tubes. WVe prefer to make the outer tube at least onethird higher than the inner, and it is necessary that the inner tube should vary in height under the difi'erent conditions in which it is required to operate, some 'places requiring a longer or shorter tube to draw the air up, as it is more or less sluggish in ascending. I

In the center of the inner tube, B, are placed the upright tubes E E E, the lower end forming an elbow, F, and passing through the tubes B and O to the circumference of the tube 0. These tubes are made from one inch to two and a half inches in diameter and aboutthree-quarters of the length of the outer tube, 0. We prefer to use three of these tubes; but any number maybe used which will accomplish the ob ject hereinafter stated.

In the use of hot-air furnaces itis well known 7 that in many places from various causes it is impossible or extremely difficult to cause the hot air to ascend freely. Among others, the most common causes are registers too remote from the furnace, the hot air not having force enough to get through the great length of pipe in entries and halls where there are strong down-currents of cold air, &c.; and "it is the particular object of the inner tube, B, to overcome this difficulty, which it accomplishes by protecting the mouth or outlet of the register from the currents of cold air near the floor, and by making a conducting-tube higher than the floor to draw up the warm air, and by the combination, with the inner tube, B, of the outer tube, 0, a thorough circulation of all the air in the apartment is made. The lower end of this tube being perforated, a current of cold air from the lower part of the room is drawn up through the space H, combining the hot and cold air previous to its passing into the room, and avoiding the injurious effects of the highlyheated air from the furnace, and this combination of the hot air from the furnace I with the cold air in the lower part of the apartment is made more perfect by the use of the tubes E E E. These tubes are placed so as to receive the direct heat of the hottest part of the ascending current of air, and by the heat a strong draft ofair is made through them,which becomes thoroughly heated previous to reaching the outlet of the tubes, and is then thoroughly mingled with the ascending current of! air direct from the furnace, and the apartment is more equally warmed, a thorough circulation is made, there is better ventilation, and the injurious effects of highly heated air avoided.

It is obvious that the exterior ofthe pipe 0 let-pipes of hot-air furnaces of the upright tubes B and C, the outer tube being perforated at the lower end in the manner specified.

2. Placing in the inner tube, B, the tubes E E E, the whole arrangement operating in the manner and for the purpose substantially as Set forth.

WILLIAM B. KEHEW. CHARLES -H. FIFIELD.

YVitnesses:

JAMES RoPEs, R0131. OSGOOD. 

